The present invention relates to an open-end spinning device as well as to a process for the temporary receiving of a yarn by means of such a device.
With open-end spinning devices, it is normal practice to have a service unit patrolling alongside a plurality of identical open-end spinning devices so as to be able to perform maintenance tasks at each one of these open-end spinning machines when necessary. For this purpose, the service unit is, as a rule, provided among other things with a yarn suction pipe that can be brought from a resting position within the contours of the service unit into a working position in which it is located in close proximity of the yarn path (DE 196 34 300 A1). This yarn suction pipe has, e.g., the task of preparing a length of yarn for the piecing return feeding and of temporarily storing yarn excess produced during piecing, until it is used up due to the difference in speeds between a device drawing the pieced yarn from the spinning element and the bobbin.
It is a principal object of the present invention to further develop the known suction device and to create a process for the temporary receiving of a yarn by means of such a device, so that it becomes possible for the device to handle additional tasks. Additional objects and advantages of the invention will be set forth in part in the following description or may be obvious from the description, or may be learned through practice of the invention.
This object is attained through the invention by having the yarn suction pipe movable within at least one additional operating plane. Due to the fact that the yarn suction pipe can be moved not only within one single operating plane but can be brought out of it and into at least one additional operating plane and can be moved within that plane, the yarn suction pipe is capable of carrying out tasks in a further operating plane offset in time relative to tasks to be carried out in a first operating plane.
Preferably, the operating planes, of which at least two are provided, of the yarn suction pipe are placed at an angle relative to each other so that they form an angle between them. By xe2x80x9cangle,xe2x80x9d an angle value is understood as being greater than zero and smaller than infinite.
In a further development according to the invention, the resting position of the yarn suction pipe is provided in proximity of the interface of two operating planes of the yarn suction pipe and/or is provided only in one single operating plane. This results in space-saving advantages.
Preferably, the operating positions are established in two operating planes that take into account the traversing range of the yarn traversing guide. This makes possible a soft transfer of the yarn to a traversing guide in one operating plane when the full bobbin is set on the winding roller, while in the other operating plane the yarn extending from the yarn guide to the bobbin driven by the winding roller is not within the traversing range of the traversing guide.
In a further development according to the invention of the open-end spinning device, the yarn suction pipe can be controlled by a control device in accordance with a previously prepared program, so that it is taken into one of the operating planes provided to carry out the operating movements for that operating plane.
For various tasks to be carried out by the yarn suction pipe, it suffices if it can merely be taken from its rest position into one single operating position. However, in order for the yarn suction pipe to be able to handle more complex tasks, it is an advantage if the yarn suction pipe is also able to assume several operating positions, one after the other, in at least one of its operating planes.
In the interest of a simple design, the yarn suction pipe can be mounted on a swivel pin so that it can be swiveled.
The movement of the yarn suction pipe from one operating plane to another operating plane can be effected in various ways, e.g., by moving it along a guiding system. In a preferred embodiment of the device according to the invention, it is possible to provide for the yarn suction pipe to be movable along its swivel pin or around an additional swivel pin supporting the swivel pin of the yarn suction pipe into an additional operating plane. It may be advantageous to install this additional swivel pin essentially parallel to the axis of the winding roller.
The apparatus described above makes it possible to carry out a process according to the invention in adaptation to different operating phases of the operating process. The yarn suction pipe is brought into the corresponding operating plane in a sequentially synchronized manner, in which it then carries out its operating movements provided for this operating plane and this operating phase. In this manner, the yarn suction pipe can carry out operating movements different from the ones carried out at other locations, and can thus carry out completely different tasks.
In another variant of the process, the yarn suction pipe is brought into the same operating plane to receive the yarn drawn off from a bobbin, independent of the operating plane to be occupied for the execution of certain operational movements.
According to a further embodiment of the invention, the yarn suction pipe can execute the operating movements required for the formation of a piecing reserve or the temporary storing of a yarn surplus occurring briefly during piecing in the same plane in which it had previously taken up the yarn presented to it. In order to constitute a yarn end reserve on the full bobbin, the yarn suction pipe can be transferred from the operating plane in which it had previously taken up the yarn drawn off from a bobbin into another operating plane in which it imparts its operational movements.
The device as well as the process according to the present invention makes it easily possible for one and the same yarn suction pipe to carry out entirely different tasks at different times. At the same time, the design of the device is simple and space-saving, since, instead of a plurality of yarn suction pipes with the appertaining terminals and their controls, only one single such yarn suction pipe is required for a number of different tasks.